Field of the Invention
The present invention relates to an imaging method. More particularly, the present invention relates to an X-ray phase-shift contrast imaging method and the system thereof.
Description of Related Art
Mammography employs low-dosage X-ray (about 0.7 mili-sievert) to examine the human breasts, mainly woman's breasts, which is able to detect various breast diseases, such as cancers and cysts. Mammography has been an important diagnostic instrument responsible for the early detection of breast cancer and consequently the much enhanced survival rate for the patients diagnosed with breast cancer.
In mammography, like X-ray examinations, the ionized radiation is applied to the human body and the accumulation of the radiation has to be considered. The relatively high ionization dose of mammography may initiate radiation-induced carcinoma. Also, for patents with thick and dense tissue that does not offer a clear image, high error rates in cancer diagnosis (at least 10% of false negative rate) greatly reduces the benefits of mammography. The dose problem makes the question of whether or not to use it, when to use it, and how often to use it a troublesome issue.
If mammography dose can be reduced dramatically, and also enhance image resolution, it would greatly improve the woman's healthcare in a highly cost-effective manner.
On the other hand, the global market for mammography equipments is pretty huge as up to 3300 units of equipments may be sold each year and the unit price of the digital mammography system is expensive. Hence, the demand for the mammography system of lower costs and high 3-D resolution is rather high.